loop for column substraction of a matrix

Hi,

Sorry, I think I misunderstand your question (after reading Rui's solution).

You can also try any of these to get the result if this is what you meant:
set.seed(1)
mat1<-matrix(sample(1:500,380,replace=TRUE),ncol=38)
res1<-t(do.call(rbind,lapply(1:ncol(mat1), function(i) mat1[,i]-apply(mat1,1,sum))))
#or
res1<-sapply(1:ncol(mat1), function(i) mat1[,i]-apply(mat1,1,sum))
#or
res1<-mapply(FUN=function(i) mat1[,i]-rowSums(mat1), 1:ncol(mat1))
A.K





----- Original Message -----
From: eliza botto <eliza_botto at hotmail.com>
To: "r-help at r-project.org" <r-help at r-project.org>
Cc:
Sent: Friday, October 5, 2012 4:05 PM
Subject: [R] loop for column substraction of a matrix


Dear useRs,


I have a matrix with 38 columns and 365 rows. what i want to do is the following.....

1. subtracting from each column, first itself and then all the remaining columns. More precisely, from column number 1, i will first subtract itself(column 1) and then the remaining 37 columns. Afterwards i will take column number 2 and do the same. In this way i want to proceed till 38th column.
2. i want to print the resulting matrix on A4 paper.

Bundle of thanks in advance.

best regards
eliza


                           
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